Dr. Gregory Thornton is introduced as the new CEO of Baltimore City Public Schools at John Eager Howard Elementary School. He was previously the superintendent of Milwaukee Public Schools. (Kim Hairston/Baltimore Sun video)

— Newly named to head Baltimore's public schools, Gregory E. Thornton has unfinished business in the district he is leaving behind after 31/2 tumultuous years.

Wearing a red T-shirt, he arrived Friday at a school where, to peals of laughter, the 59-year-old would join kids in a "jump rope-a-thon." But, as so frequently happened during his tenure, there were political hoops to jump through first.

"How are we doing?" Thornton asked a state senator he spied in the welcoming crowd.

It was not so much a pleasantry as a pulse check: How are we doing, he meant, in thwarting two bills that would close public schools and sell empty facilities to private schools that accept vouchers?

In a brief exchange, the senator mentioned a potentially worrisome legislator, and Thornton said he'd already talked to her the previous night. And then, it was time to "make some noise" as he exhorted the school crowd who had gathered to jump rope in honor of a phys ed teacher who started the tradition 35 years ago.

It was just another day navigating the complicated terrain of Milwaukee Public Schools.

Critics and admirers alike say Thornton is energetic, deliberate in his decision-making and ultimately caring toward the children in the 165-school system. They also say that he has headed the district during a particularly challenging time — when, as one parent put it, "hating MPS has been a regional pastime."

Where they differ is in assessing how he has negotiated the many political and budgetary land mines in his path.

"I think he was trying to think creatively in the context of a complicated situation," said Keisha Krumm, lead organizer with the community group Common Ground, which worked with Thornton on improving a tutoring program in the schools. "He's not an ideologue. There was an energy and passion to his work, but also a pragmatism."

He was hired in 2010, just as the Milwaukee mayor was trying to wrest control of the district from the school board. Soon, the state's governor would cut hundreds of millions of dollars in education funding and dismantle the collective bargaining rights of teachers and other public employees.

Meanwhile, conservative groups were increasingly successful in pushing their privatization agenda — expanding a voucher program that allows students to use public funds for private school tuition, and turning failing schools over to outside operators and companies to run as charters.

By many accounts, Thornton proved adept at negotiating this fractured environment, a pragmatist who would find a middle path through conflicts — while both sides would sometimes emerge not knowing where he personally stood.

But detractors would argue that even if he was hamstrung by a political situation not of his own making, he could have done more since taking over the Milwaukee schools.

"I think most everyone would agree that his tenure was short and without a significant accomplishment," says Charles Szafir, education policy director at the Wisconsin Institute for Law and Liberty, a nonprofit advocating for limited government, free speech and education reform. "He was toeing the line of the education status quo."

Szafir's assessment, though, is hardly unchallenged. In fact, he represents what many believe is part of the problem: a shift of more students toward private and charter schools robbing conventional public schools of much-needed funds, enrollment and attention.

"There is an all-out war on the public schools, an effort to undermine public schools, to drain resources," says James H. Hall Jr., president of the Milwaukee chapter of the NAACP. "And it is not letting up."

Indeed, the percentage of children going to conventional Milwaukee schools is dropping 1 or 2 percentage points every year, said Alan Borsuk, a senior fellow in law and public policy at Marquette University Law School who has been tracking the trend.

Only about 60 percent of Milwaukee students attend regular public schools. About 25,000 students use publicly funded vouchers to attend religious and private schools. Additionally, students can transfer out of the city schools into suburban schools if there are slots available, and there's a broad range of charter schools.

In Baltimore, by contrast, 75 percent of the district's students attend regular public schools.

Thornton took fire from both sides of the public-private debate. Privatization advocates complain that he blocked charter schools and in one widely publicized issue, refused to sell an empty public school to a charter that wanted to expand into it. On the other hand, public school supporters complain that he was all too quick to turn a failing school over to a company or outside operator to convert into a charter.